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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Posted on 22 September 2012 by John Mason

The truth is incontrovertible. Panic may resent it, ignorance may deride it, malice may distort it, but there it is. Winston Churchill, 1916.

Late summer has long been known in media circles as the Silly Season, when any old story, embellished a bit here and a bit there, is trundled out to fill column space normally occupied by the graver matters of politics and business.

In the world of climate science, late summer is of course rather more important, marking the peak of the annual sea-ice melting season of the Northern Hemisphere, and this year has been extraordinary, with the canary in the coal mine tweeting louder than ever that something is seriously amiss with the climate.

With Arctic sea-ice having reached a record low extent, area and volume, several weeks ahead of the usual end-of-melt date, the Blogosphere has been ablaze with lengthy discussions of this event and its potential and worrisome ramifications. There have also been mass-outbreaks of denial accompanied by varying degrees of silliness, as one might expect when faced with an event like a record Arctic melt-out. Many commentators could see the meltdown approaching, both in the Arctic and around parts of the Blogosphere, with Gareth Renowden over at Hot Topic speculating in early August as follows:

"When Arctic sea ice area sets a new record low in the next couple of weeks, the usual suspects will say: “You can’t trust area, sea ice extent is the only valid metric“.

When Arctic sea ice extent sets a new record low in September, the following arguments will be run in parallel:

1) There will be a frantic search for a definition of extent in which a new record was not set

2) There will be a complaint that the satellite record has been blighted by the failure of a sensor and the calibrations needed to get a new sensor in operation have corrupted the record

3) It will be claimed that it was all caused by the major Arctic storm that hit in August, and thus can’t be attributed to global warming

4) It’s cyclical — it’s all happened before, in the 1930s, and is therefore nothing unusual

5) That it’s irrelevant, because it’s not global and not happening where anyone lives so can’t possibly matter.

When the sea ice extent and area anomalies blow out to record levels in early October because of the delayed freeze-up, there will be silence.

When the re-freeze starts, and the Arctic basin is covered in ice once more (early December), Anthony Watts will report on the record rate of ice formation, calling it a “stunning recovery“."

They go on in strange paradox, decided only to be undecided, resolved to be irresolute, adamant for drift, solid for fluidity, all-powerful to be impotent. Winston Churchill, 1936.

How closely did Gareth's predictions above conform to the reality on the media airwaves? In this post-minimum-declared Blogosphere round-up, we take a light-hearted look.

In terms of searching for definitions of extent that failed to break the record (prediction #1), one set of data became increasingly popular in fake-sceptic circles - the IMS data. However, in clutching at this particular straw, its eager proponents overlooked a rather important point: IMS (acronym for Interactive Multisensor Snow and Ice Mapping System) is specifically intended for marine navigation, not climate monitoring, purposes. The eminently sensible idea is to map as much ice as possible as accurately as possible each day and week in support of ships (particularly DoD ships) operating in and near ice-covered waters. As a consequence, areas with too low an ice concentration to show up as extent on the NSIDC, DMI or JAXA dataplots are very sensibly counted as icy because of the potential hazard to boats not equipped to sail through such waters. In other words, IMS is an orange in amongst a basket of apples. Or (false balance alert), as IMS fan Steve Goddard put it in his so-called 'Real Science' blog on August 25th:

"The National Ice Center is in the business of being accurate and saving lives, while [the University of] Bremen is in the business of obtaining global warming grant money."

That is a comment that needs no further comment from me. Meanwhile, evidently unflattered by such favouritism, the IMS dataset went on to take a nosedive all of its own and broke its record in early September:

Prediction #2 gained relatively little traction but maybe that was because prediction #3 - blaming the situation on the cyclonic windstorm that occurred in early August - was so easy to run with. But hold on a moment. The melt-rate prior to the storm was such that a record was inevitable anyway - the storm only increased melt-rates for a few days.

Furthermore, whilst such storms are indeed uncommon, the early August gale was not an unprecedented event. Who says so? Paul A. Newman, chief scientist for Atmospheric Sciences at NASA's Goddard Space Flight Center, estimates that there have been about eight storms of similar strength during the month of August in the last 34 years of satellite records. And there's a second factor: ice-quality (an often overlooked parameter), Claire Parkinson, a climate scientist with NASA, commented, “decades ago, a storm of the same magnitude would have been less likely to have as large an impact on the sea ice, because at that time the ice cover was thicker and more expansive.” Indeed. Two metre-thick robust pack-ice is a lot harder to disintegrate than the thin, slushy rubbish that this year's storm had at its disposal. In summary, yes the storm was a minor factor in the magnitude by which the record was broken, but only because the ice was already in such a poor state. An impressive record minimum would have occurred, storm or no storm.

Owing to past neglect, in the face of the plainest warnings, we have entered upon a period of danger...Winston Churchill, 1936.

With regard to prediction #4, we had John Christy making claims about low minima in the late 1930s-early 1940s (the lowest minimum, in 1940, was in fact approximately 9.8 million square kilometres as opposed to 3.4 million square kilometres in 2012), although he didn't get too specific, perhaps for obvious reasons. He was paraphrased by a Sunday Times journalist thus: "anecdotal and other evidence suggesting similar melts from 1938-43 and on other occasions". Skeptical Science posted a detailed debunking of Christy's claims early this September.

However, as with many such claims that appear in the media, they tend to spread, like a bad cold. The quote below is transcribed from a BBC Newsnight discussion (about Arctic sea-ice, complete with all the familiar graphics), broadcast on September 5th, in which UK Conservative MP Peter Lilley took part. As readers can see, he managed to slip in Christy's claim, but for some reason he tagged it to the wrong end of the planet. However, he also brought in something that was not predicted by Gareth, or anyone else for that matter. Take a look:

"you have presented something which purports to be new evidence that contains nothing new, which is tendentious, not peer-reviewed, by a well known alarmist and absolute bunkum compared with the IPCC....the IPCC says sea ice is predicted to shrink in the Arctic and Antarctic under all scenarios and in some projections Arctic sea ice disappears almost entirely by the latter part of the 21st Century. They then present a graph of all the different projections and none of them show it is melting before the year 2070 on a regular basis in the summer. Now of course it used to melt from time to time in the Thirties when it was much warmer in the Antarctic. So you've got a very tendentious piece of presentation there by someone who's disagreeing with the IPCC's science."

Whoever would have thought of that as a tactic - if events prove worse than IPCC projections, then go with what the IPCC said! What will they think of next? Especially when the self same Peter Lilley, writing in the Wall Street Journal in December 2009, opined:

"The whole U.N. Intergovernmental Panel on Climate Change process could not be better designed to institutionalize groupthink on a global scale."

Is this the same person here? Anyway, onwards.

How about advancing the "it not being a global effect" (prediction #5) argument? One word: Antarctica. Suddenly, every fake-skeptic worth his or her salt had their eyes fixed on this gigantic ice-cube sat atop a pole-straddling continent surrounded by ocean. Note here that, in drastic contrast, the Arctic is an ocean surrounded by continents - the dynamics are completely different. To continue however: as luck would have it, there was a new paper to talk about on climate change in the West Antarctic Peninsula, largely based upon hydrogen isotope values from an important new ice-core (post and discussion at Realclimate).

The findings were also discussed at the Watts Up With That (WUWT) website. For anybody unfamiliar with the site, it endlessly trots out wild hostility to the notion that global warming, as a consequence of the reckless burning of fossil fuels, is a serious threat to mankind - despite what the science says. So, how went the discussion? Site host Anthony Watts commenced with:

"Regarding that rapid warming of 2C in the last 50 years, just remember that most weather stations in the Antarctic are near humanity, and humanity requires warmth to survive. For example [photo, annotated in purplish we assume by Watts]:

That was it, verbatim. A bit short, but there we are, left to draw our own conclusions. So what are we to make of it? Was Anthony Watts seriously trying to tell us that the West Antarctic Peninsula suffers from an Urban Heat Island effect because a few hundred scientists hang out down there? The photo he used appeared to show a temporary field camp, something akin to the Everest Base Camp and hardly urban in nature. Whereabouts was it? And what does it have to do with a long-term temperature reconstruction based upon hydrogen isotopes from an ice-core? All very mysterious.

However, following the usual stream of comments (general and unending theme = 'those darned warmistas are at it again'), an important clarification was posted, which we reproduce here in full:

Dear WUWT

I guess I owe the world a humble apology for personally contributing so much to the urban heat island in Antarctica, and hence to misinterpreted climate records.

The badly sited meteorological screen in your photo is at an Australian summer camp in the Northern Prince Charles Mountains, near Mt Jacklyn – in the background. Temperatures measured here were for local information of pilots and field parties only – it is useful to have an idea of how many layers of clothes to put on before exiting your Antarctic shelter. Temperatures here were only measured for less than 2 months over a couple of seasons and have NEVER been used for any climate record.

This photo was taken in the 1988/89 austral summer when I, and a colleague Andy, lived in the UNHEATED shelter nearest to the meteorological station. I didn’t realise that I was so hot that my body heat could influence temperatures measured on the Antarctic Peninsula, thousands of kilometres away. It must have been Andy!!!

Ian

A little geographical research shows the location of this interesting area of East Antarctica:

Thanks to Ian for clearing that one up!

It would be unfair to omit the fact that Antarctic sea-ice extent has been high, impressively so if certain blogs are to be believed. Beware! During the current, about-to-end Southern Hemisphere winter, it peaked at about 19.4 million km2, after a minimum of about 5 million last summer (edited 22/09/12 - thanks to Skywatcher in the comments below for spotting the error). Some people seem easily impressed. The 1979-2000 average maximum is around 18.5 million km2. In the Arctic, the maximum has remained this past 30 years at 13.5 million to 14.8 million km2, but the minimum this year is 3.4 million km2, against a 1979-2000 average of approximately 6.75 million km2. That seems to me a rather more substantial figure. It has involved a meltdown of over ten million square kilometres of sea-ice, leaving just three and a half million behind. (addendum 22/09/12: Tamino has covered the Arctic-Antarctic difference in far more detail here.)

So - back to the Northern Hemisphere, and coincidentally, the declaration of a record Arctic sea-ice extent (August 26th) came in a week where the American Meteorological Society released a statement about climate change on August 27th, in which the concluding remarks sum up the situation as follows:

There is unequivocal evidence that Earth’s lower atmosphere, ocean, and land surface are warming; sea level is rising; and snow cover, mountain glaciers, and Arctic sea ice are shrinking. The dominant cause of the warming since the 1950s is human activities.

"Seems almost a planned effort this week, Sea Ice, [Hurricane] Isaac, and now the AMS statement."

As Scotty of Star Trek fame would have said - 'Ye cannae change the laws of physics.'

How about the other arguments that Gareth missed? One I did hear reported over at Neven's Arctic sea-ice blog was the claim that 450 more cubic kilometers of ice volume went away in 2010 (18,974 km3) than have so far this year (18,523km3), meaning - wait for it - that the ice is in "recovery". Now then. If I were to melt a whole ice-cube in 2011 and then melt a half ice-cube in 2012 then I'd have melted less ice in 2012 but still have ended up with nothing. Fail.

"The Earth’s surface area is about 510 million square kilometres. The Arctic ice extent at it’s [sic] minimum is currently around 3 million square kilometres. So we’re talking about 0.6% of the area."

Anyone spot the flaws with this? Firstly, Arctic sea-ice is a feature specific to water. Secondly, it's not the extent after melting, but before that is important, because it is the difference between the two that represents the amount of albedo-loss over the planet's waters, albedo being the proportion of incoming solar energy that is reflected by a surface (as opposed to being absorbed) during, in this case, the Arctic summer.

The surface area of Earth that is water-covered is approximately 361,132,000 square kilometres. Last March, the Arctic sea-ice maximum was approximately 14,440,000 square kilometres. Doing the maths:

(14,440,000/361,132,000) x 100 = 3.998%

So that's almost 4% of the surface area of Earth's water over which the albedo value can undergo dramatic change. Albedo is expressed in values between 0 and 1; snow-covered sea-ice has an albedo of 0.9, bare sea ice has an albedo of 0.5 and open sea water has an albedo of 0.06. That means that snow-covered sea-ice only lets 10% of incoming solar radiation through into the water; bare sea-ice lets about half through but open water lets a whopping 94% of incoming solar energy in. This year, the drop in Arctic sea-ice extent has been from a high of 14.44 million sq km to a low of 3.4 million sq km - a loss of over 75% of that useful high-albedo area. So forget about 0.6% - it is a meaningless figure!

But perhaps the last word can be awarded to Dr Judith Curry of the blog Climate etc, in an interview with Yale Environment 360 on August 30th:

“I don’t think this apparent record sea ice minimum is of particular significance in our understanding of climate variability and change of Arctic sea ice.”

What a strange choice of words. Apparent record? The National Snow and Ice Data Center (and these guys know what they're talking about - it's their job) had confirmed the record had gone in a press release four days previously. Eye off the ball, maybe? Who knows? For now, let's use a couple of images to explore this choice of vocabulary:

Now that the minimum has passed we enter the long darkness of the Arctic winter. The sea surface will once again start to refreeze. There should be a final maximum extent by mid-March 2013 of, as consistently recorded over recent decades, 13.5 to 14.8 million square kilometres, at least 10 million km2 of which will be thin, melt-prone first-year sea-ice. As to next year's melt season? In this particular case, the models have struggled - they have underestimated the metdown, as the graph below, borrowed from Neven's Arctic sea-ice blog, demonstrates. However, NSIDC Arctic specialist, Dr Julienne Stroeve, in a recent Guardian interview, commented:

"We can expect more summers like 2012 as the ice cover continues to thin. The loss of summer sea ice has led to unusual warming of the Arctic atmosphere, that in turn impacts weather patterns in the northern hemisphere, that can result in persistent extreme weather such as droughts, heatwaves and flooding."

The era of procrastination, of half measures, of soothing and baffling expedients, of delays, is coming to its close. In its place we are entering a period of consequences. Winston Churchill, 1936.

To conclude, for most of the media world, late summer is the silly season. Unfortunately, in some parts of the blogosphere, it appears to have become a permanent state of affairs! But there's one final prediction of Gareth's remaining to be confirmed. Will a 'Stunning Recovery' be widely announced as we head into winter 2012-13 and the sea refreezes, as it is supposed to? For the answer to that, only time will tell.

Comments

Another part of Judith Curry's comment is as follows:
"Judith Curry said that while global warming is “almost certainly” affecting Arctic sea ice, she cautioned that there is a great deal of annual and decadal variability in sea ice cover. She said that the next 5 to 10 years could see a shift in Arctic sea ice behavior, though exactly in which direction is difficult to predict."

If she thinks there will be a "shift in behavior" it can only go up, because we have already seen a shift downward since 2007. In addition, looking at your chart of the IPCC prediction, the red line shows almost no Decadal variability after the initial period. The 9 year average shows no variability.

#6: "Look out behind you! The Antarctic is growing!"
This tactic has become popular at places like Jo Nova. But its not just Antarctica they point to. They also choose to divert their eyes from West Antarctica and instead focus only on East Antarctica. One can only wonder which direction they will choose to look when the Antarctic inevitably starts doing what is expected in a more obvious way. No doubt they will rely more heavily on #1-5.

You illustrate a central position that is used for denial, the misdirection and confusion allowed when a particular adjective is applied. Curry’s use of “apparent” is a subjective qualifier that suggests to the reader or listener that there may be some questions as to the relative merit of this “apparent record”. Suddenly it is no long an empirical observation, now it is a “possible” conclusion and one that opens the door of doubt.
Reading WUWT and SKS one is drawn to the tonal difference between the two. Where the former enjoys subjective and pejorative insights painted freely with these kinds of adjectival colorations and formulated in the conspiracy of motivation, the later details objective analysis of metrics helped along by a moderated insistence on a discourse that leaves subjective opinion at the door.

Though he avoided the loaded adjective I couldn’t help but laugh when I took a look at the comments by Watts where he feels the need to mention that “most weather stations in the Antarctic are near humanity, and humanity requires warmth to survive” or “The Antarctic Peninsula is the most populated place in Antarctica.” I was struck by not only the absurdity of mentioning “humanity needs warmth to survive” but I was left trying to discern how these factoids are suppose to relate to the issue of ice loss or the supposed viability of measuring stations.

Anytime I see a discussion involving Watts and "surface stations" I can't help but be reminded of Tamino's punishing review of his surfacestations.org lead photo of two California sites. Thanks to SKS it's archived here http://web.archive.org/web/20080613192826/tamino.wordpress.com/2007/07/30/surface-stations/ Urban heat index and Antarctica...that too will require some magic....

An article by Matt Ridley in the WSJ is right up there in the silliness stakes. It appears that in a effort to play down the impact of the loss of Arctic ice, Ridley is quite happy to make a complete fool of himself.

Here is an example.
"Although an entirely ice-free Arctic Ocean during at least one week a year is still several decades away at this rate, we are halfway there after just three decades."

After numerous distractions involving arctic foxes and amphipod crustaceans, he gets to his main point.

"But is the current rapid retreat caused only by warming? At least some of it might be caused by soot from dirty, coal-fired power stations. Some scientists have noticed that the decline in Arctic sea ice correlates better with the rapid growth of coal consumption in China than it does with global temperature. As the argument goes: Soot falling on white ice darkens it, which results in faster melting in summer sun.

Correlation does not always mean causation, but if soot is contributing to sea-ice melt, then it is moderately good news, because cleaning up soot emissions from power stations could be both cheaper and quicker than cutting carbon-dioxide emissions."

Great article, John, and some of the links in the comments have me giggling, too. Only one complaint, your canary metaphor is a little muddled. If there is something wrong in the mine, the canary doesn't tweet louder, it keels over. I'm afraid one of the canaries is dead.

The last two Arctic sea ice news posts at WUWT have been pushing the turning point of the big refreeze. The first one asked if the late season melt had "turned the corner" yet. No, it hadn't. A couple of days ago the agenda was a bit starker, headlining with

2012 Arctic sea ice minimum reached, it’s all gain from here

WUWT must downplay this in every way possible.

Latest daily extent from MASIE, which Anthony Watts himself gave the gold seal of approval, has the lowest extent for the year.

It's not that WUWT was wrong, it's that Watts, who should know so much better considering the amount of text devoted to emphasising weather influence on September minimum at WUWT, needs so desperately to control the narrative he sets himself up for the gaffe.

I should be a bit careful myself - that last value could be adjusted upwards tomorrow, but not by enough to mar the point.

Well spotted! I was enquiring after the health of said canary - Anthony assured me that it was "just resting". I have since taken the liberty of examining it properly, and I discovered that the only reason it was sitting on its perch in the first place was because it had been nailed there!

Skywatcher - thanks for spotting that! Have edited the text with date of edit flagged. It was a last-minute addition that I got from eyeballing the NSIDC Antarctic graph. Next time I shall take my time with such alterations!

The post points out that summer Arctic storms of this strength are uncommon but not unknown. However, the trend is for more Arctic storms whatever the season according to 'Sea ice drift in the Arctic since the 1950s.' Hakkinen et al 2008. who say "The study finds that both parameters (ice drift and wind stress) show gradual acceleration over last 50 years. Significant positive trends are present in both winter and summer data.The major cause of observed positive trends is increasing Arctic storm activity over the Transpolar Drift Stream caused by a shift of storm tracks toward higher latitudes."

And if, as these denialists on Wattsupia are saying "It's the storm what done it, guv!" can the massive impact of the storm be seen? This graph of Arctic Ice Area (usually two clicks to 'download your attachment') starts from the beginning of August. The storm struck on the 5th, not that you'd notice from the graph.
The graph as I type is up-to-date & so does show the first few days of the freeze which will be worthy of monitoring in coming weeks to see if the severe melt will impact the following freeze.

Too true. But prior to shuffling off this mortal coil, joining the choir invisible, and becoming an ex-canary, he was better at detecting the danger of greenhouse gas accumulations (in this case, methane) than Mr. Watts apparently is. I'd pine too.

A small criticism of the 'Artic Sea Ice Extent' and 'How "Skeptics" View Artic Sea Ice Decline" graphs. Both graphs could have there Y axis start at zero, the ice extent starts at 2 million km2 and the skeptic view at 3 million km2.
I know graph makers are probably trained to avoid the "wavy line a the top" effect but it smacks of graphing tricks to emphasize your point. We shouldn't need to resort to graphing 'tricks'.

#28 - the same could be said for NSIDC & JAXA Arctic sea-ice plots: however, within a few more years the aforementioned organisations, plus Dana, creator of The Escalator, are 'all gonna need a bigger graph'!

If Matt Ridley was realy influenced by what he read in Hansen 2003 (possible), then, he managed to read just the first two sentences of the abstract! The last sentence of Hansen 2003 abstract sais:

However, soot contributions to climate change do not alter the conclusion that anthropogenic greenhouse gases have been the main cause of recent global warming and will be the predominant climate forcing in the future

which Matt probably failed to understand, or rejected it as the unexplainable contradiction of his pre-conception of "all-mighty Chinese soot"! In WSJ, they have a strong incentive to blame everything on China.

Chris- When I wrote the note @ 18, I had no idea that someone was actually using the meme...I was simply trying to add a perception of the memes that were possible to John Manson's list. I read the last two sentences as well, but all of us are all too familiar with selective quotations and decontextualization of quotations. Thanks for sharing that the meme is actually in use. Perhaps you and John can add some text to the article, and it can be included in a 'myth buster' index.

Would certainly be good for readers to post any other daft Arctic sea-ice arguments they have encountered in this thread. I've today come across someone posting 'that' graph of sea ice area anomaly where the scale of the Y-axis is shrunk so as to show there's nothing happening! Have lost count of the number of times Tamino has debunked that one!

Just to expand on what happened with Ian's first hand clarification on WUWT..... Anthony posted in reponse "you kids don't know what you are talking about". Says it all really I'm afraid.
Anthony also gave me a new perspective and meaning of the phrase "All science is either physics or stamp collecting"

mikeh1@7 has shown, that Matt Ridley from WSJ had fallen victim of that myth. Together with your Hansen 2003 meme, it sounded funny. Out of suriosity, I've read Matt's article (normally I don't read WSJ because it's waste of time) to check the source of his opinion, and here it is, his entire attribution:

Some scientists have noticed that the decline in Arctic sea ice correlates better with the rapid growth of coal consumption in China than it does with global temperature

A little disapointment here that Matt did not cite verifiable source but rather "Some scientists" limbo. But no surprise here: deniers like him often practice such reporting.

So we cannot conclude that Matt Ridley lacks basic skills to understand a simple 5-sentence abstract. But said conclusion can be declared probable. In fact "Some scientists" can also mean Hansen 2003.

Panzerboy #28: There are no "graphing tricks" involved... this post pulls together graphs from multiple different sources covering different time frames and even different units of measurement (square miles vs square kilometers). Thus, implying that the 'failure' of these different sources to all use the same starting point for the Y axis is some kind of deception makes no sense.

It is standard practice to produce graphs scaled to the range of values observed or likely to be observed. When the NSIDC graphs were first plotted a few decades ago you could as 'easily' have argued that the Y-axis should go up to 20 million square miles (a value not seen for centuries) as down to 0. Now that the ice is in full out collapse and zero is becoming a possibility it is likely that the NSIDC will have to reframe the graph in the upcoming years... but again that is just following the need to show the full range of observed values without massive amounts of white-space above or below the observed range.

Indeed, scaling a graph well outside the range of observed values often constitutes a 'trick' because it reduces the perceived degree of change. On a scale going up to 100 million square miles the melt of the past few decades would look like a nearly flat line. Hence the standard practice of scaling graphs to fit the observed values rather than a large range around them.